Hot-water heating apparatus



(No Model.)

A. T. HENDERSON. HOT WATER HEATING APPAMTUS.

Patented; May 29, 1894.

3 sheets-Sheet, 1.

(,No Model.) 3 Sheets-Sheet 3. A. T. HENDERSON. HOT WATER HEATJNG APPARATUS.

'Patented May 29, 1894 ilnrrna rrnftns Pasteur Diarrea.

` ALEXANDER T. HENDERSON, 'Olf DETROIT, llllClllG-AN.

HOT=WATER H EATlNG APPARATUS.

SPECIFCATlON forming part of Letters latent No. 520,677, dated vay 29,1894.

Application filed July 28, 1892. `Serial No. 441,516. (No model.)

and useful Improvement in Ilot-Water lleat- -ing Apparatus, of which the following is a specioation. Y

My invention consists in an improvement in het water heating apparatus, hereinafter fully described and claimed.

Figures l and 2 are sections through the eX- pansion tank of a hot water heating apparatus. Fig. 3 is a side elevation. Fig. i is a seetion on line 9:-703, Fig. 3, and Fig. 5, is a diagram to show the connection of the tank with a boiler and a radiator.

lot water heating apparatus have been' operated upon two systems: ln one the expansion 'tank (which is placed at the highest point of the apparatus) is constantly open to the outer air, and the temperature of the water can never rise above 212. This system gives a soft, pleasant heat, but requires a large heating and radiating surface to cornpensate ferthe low temperature of' the heating agent. -ln the other system the expansien 'tank is closed and provided with a safety valve, by means of which the water can be raised above 212U (without passing into steam) until it reaches the liniit at which the safety valve is set. This system does not need as rnueh heating and radiating surface as tl e first named, but is dangerous for the reason that as expansion tanks are usually placed in garrote, and are rarely ever examined, the` safety valves become corroded to their seats and frequently refuse to work, thereby causing great danger of explosion.

The object of this invention and ofthe two cognate inventions, for which applications were led simultaneously herewith, is to Coinbine the advantages of the two systems without the danger of the closed system, and the principle of my invention consists in providing 'the expansion tank of a hot water systein with a safety valve, which at a low temperA ature is constantly open through the ,oontrae ion of seine' of the parts, which closes when a steam temperature is approached, and which acts while steanr temperature is maintained, as a safety valve, andywhieh opens through the contraction of seine of the parts when the 'system is allowed to wholly or partially cool.

Frein this it is evident that as the safety valve remains open during all the time the apparatus is not in use, there is no opportunity for the valve 'to rust or stick to its seat.

Referring te the figures, A represents an expansion tank whieh'in practice is suitably connected with a boiler and one or'inore radiators. For the purpose ot' exhibitingroue connection ofthe parts l have indicated in Fig. 5 a boiler B connected bya pipe A with the tank A at the point B, Figs. l and 2. The tank is also connected by a pipe or pipes A2 with a radiator or radiators B2.

ll represents a safety valve of the lever type, (though the spring type may be used,) secured to tank A. v

C represents a metal rod fastened at one end to the bottom of tank A and extending out beyond the other end of said tank, preferably through a stuffing box O.

D represents a lever pivoted at one end to a post G carried on tank A, and at its other end pivoted to the long arm of lever E, ful- @ruined to a post F also carried on tank A; The short arin of lever E engages with the safety valve lever L, which by means of the adjustable weight forces down the valve stein J. The end of rod C is connected with lever D near its fuleruin, either by being pivoted thereto, or by being slotted and embracing saidlever, or in any other suitable way.

The operation of this invention is i'ollows: `When the water in tank A is below the temperatureat whiehit is desired to bring" the safety Valve into action the rod C pulls down on lever D thus depressing the long arm of lever E and raising the short arm ot' said lever, which raises the lever L and valve stein J, thus holding the safety valve open. `When the water in .tank A becomes heated the rod C expands and lengthens, forces lever D upward, and thus permits the safety valve lever L to descend and close the safety valve, which then operates in the usual inauner, opening with an, excess of pressure and blowing off through pipe l.

Fig. 2 illustrates a modification designed to force the safety valve lever in both directions.l

In this arrangement the rod Chas a slot rc which embraces the short arm of the valve lever L, which is fulcruined on post M. The

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slot c is wider than lever L, and is so placed that when rod C is expanded sufficiently to allow the safety valve to close the upper end of slot c just' touches the upper side of lever L While the length of said slctperniits the short arm of lever L to descend freely when the safety valve'epens througlrexcessof pressure.

C re resents another expansion rod similar to Q van engaging with lever L on` theothcr side' 1o .of its fulcrunn by nieansof aV slot c so arranged that when rod has expanded sufficiently to permit safety valve t'o close rod Cvwill have expanded `suiiticiently to bringr the lower side of slot c nearly against the under side of lever "L, and a certain further expansion of said rod Cf'from excessive temperature will open the safety valve. When the temperature of the water in tank A falls bothrods contract and slierten, and rod C opens the safety valve,

zo' and holds it open until' the Water is again heated suiiiciently to again expand said rods. Fig. 3 represents a modification in which a lever N fulcrumed on a bracket M! is connected by a rod Q, pivoted at n with the le verPof a safely valve ll. The expansion rod C carries on its end a head., @having a set screw S adapted to bear on the short arrn oflever N and open the safetyk valve when rod C is cold, and to permit the Safety Valve to 3o closewlien rodOcxpands. Another-set screw Twill open the safctyvalve if rod C- beccmes unduly expanded. y

What I claim as my invention, and desire .to secure-by Letters Patent, isf l. In a heating apparatus the combination of an expansion tank,'a safety valve, and an expansion rod connected with the safety valve to hold the safety valve open when` the water in the tankis below the temperature at which it is desired to bring said valve into action,

substantially as and for the purposes set forth. 2. In a hot Water heating apparatus the coin-y bination of an expansion tank, a safety'valve, and an expansion rod having one end rigidly fastened and, having its free end connected with the safety valve lever to hold the safety valve open Whenthe Water in the tank is be- 10W the temperature at which it is desired to bring said valve into action, substantially as .shown and described. f

3. In a hot-Water or steam-circulating heating system, the combination of a safety-valve,

and means whereby the valve is automatically unseated andheld open at a low temperature and seated by a rising temperature, substantially as described.

4. The combination with the expansion tank A, safety valve H, and pivoted lever L, of the- 

